Cost-effective sensors for measuring the steering wheel angle provide relative values of the angle with respect to the position of the steering wheel at the start of ignition of the vehicle. The measured angle of the steering wheel at the start of ignition is, however, generally shifted with respect to the center position of the steering wheel (referred to as zero point shift or offset). After the start of the ignition, the sensor therefore firstly indicates a zero value irrespective of the position of the steering wheel even though the angle is not equal to zero in every case. However, the steering angle must be measured precisely (and in absolute terms) because it is used in the electronic stability program (EPS) and is highly significant for the safety of the vehicle.
DE 697 14 806 T2 discloses a method for determining the position of a steering wheel in which the center position of the steering wheel is estimated with a first predefined algorithm or a second predefined algorithm, depending on whether a calculated steering wheel lock angle is within or outside a specific interval. Depending on the algorithm used, relatively fast or relatively slow leveling off to a center position value occurs.